苯甲酸加氢催化剂Pd/C抗中毒方法研究及应用

研究了苯甲酸加氢过程中Pd/C催化剂的失活原因，针对CO引起Pd/C活性降低，开发了SRNA－5助催化剂，有效消除了反应中生成的CO对Pd/C催化剂活性的影响。并在石家庄化纤公司完成了工业试验，工业试验表明，在不改变原工业流程的基础上，通过向苯甲酸加氢工业装置中加入SRNA－5助剂，有效提高Pd/C催化剂活性，该厂每年减少催化剂直接费用1500万元。     

4-乙基-1-苯基环己醇的催化氢解

在乙醇体系中,4 丙基 1 苯基环己醇在2MPa氢气压力下200℃反应8h,完全氢解且反式选择性高,得到71.7%的反式产物和22.3%的顺式产物。考察了温度等对氢解反应的影响,发现高温有利于反式产物的生成。     

Pt/C活性催化剂催化氢化合成6-氯-2-羟基喹喔啉

以对氯邻硝基乙酰乙酰苯胺为原料，在碱性条件下经环合及催化氢化合成6-氯-2-羟基喹喔啉。采用自制的Pt／C催化剂，考察了反应条件对产品收率的影响，在85℃，1．0～1．3MPa氢气压力下进行加氢还原反应，总收率89．6％(以对氯邻硝基乙酰乙酰苯胺转化为6-氯-2-羟基喹喔啉)。     

工业化连续生产对(艹孟)烷的影响因素探讨

主要对工业化连续生产对烷的影响因素进行了研究,探讨了原料中重组分含量、反应温度、反应压力等不同条件对对烷的生成所产生的影响。通过试验确定了主要生产工艺参数为:原料中重组分含量不超过1.2%,反应温度185-200℃,反应压力9-11 MPa。     

芳香族硝基化合物催化氢化催化剂Cu-Re_mO_n/SiO_2的放大试验研究

为提高芳香族硝基化合物氢化催化剂的性能,在单铜催化剂中引入稀土元素。以15 g微球硅胶(S iO2)为载体,在Rem(NO3)n溶液中浸渍,控制温度70℃,浸渍后经二次蒸馏水洗涤,并先后经120℃干燥、830℃焙烧等工序制得RemOn/S iO2。将该载体在Cu(NO3)2溶液中再次浸渍,步骤条件同前,但焙烧温度为400℃。分别制得Cu-CeO2/S iO2、Cu-Sm2O3/S iO2、Cu-Ho2O3/S iO2、Cu-Yb2O3/S iO24组催化剂。用微分反应器在硝基苯催化加氢反应中进行评价,筛选出负荷最高的Cu-CeO2/S iO2催化剂。按小试S iO2量100倍进行放大试验,所得到的1.4 kg Cu-CeO2/S iO2催化剂,在硝基苯催化加氢反应中,一次寿命(未再生)的负荷超过目前工业生产中广泛使用的Cu/S iO2催化剂121.28%。     

苯甲酸催化加氢合成环己基甲酸的研究

采用绿色合成法,在水相条件下,在Pd/C催化剂的作用下用苯甲酸催化氢化合成环己基甲酸.通过一系列的实验,得到了较好的合成环己基甲酸的工艺条件,在该条件下,能够得到比较纯的产物和较好的产物收率.     

加氢催化剂的器外再生

介绍了国内外再生技术的发展状况，对比器内和器外再生技术的优缺点以及催化剂活性恢复率的差异，说明器外再生技术是催化剂再生的发展方向。     

Premodification of Pt/γAl2O3 with Cinchonidine for the Enantioselective Hydrogenation of Ethyl Pyruvate: Effect of Premodification Conditions on Reaction Rate and Enantioselection

The premodification of a 5 wt% Pt/-Al₂O₃ catalyst with cinchonidine (0.01 and 0.2 g g^-1 _catalyst) is described and discussed. Premodification is carried out by treating the catalyst with a solution of cinchonidine followed by solvent removal. Catalysts premodified in this way give the same ee and initial rate of reaction for the enantioselective hydrogenation of ethyl pyruvate as those using the standard in situ modification procedure. Investigations of different solvents for premodification and reaction (dichloromethane, ethanol) show that it is the solvent used for the reaction that controls the observed enantioselection. Premodified catalysts also display the initial transient behavior typically observed with in situ modified catalysts in which the ee increases with conversion in the early part of the reaction. Premodified catalysts show an enhanced rate of reaction when ethanol is used as the reaction solvent compared with in situ modified catalysts under the same conditions. Premodification using aerobic conditions gives the best results and premodified catalysts can be stored prior to use for up to a week without loss of catalytic performance.     

Pd deposited on Cu(110): a highly performant catalyst for the 1,3-butadiene hydrogenation reaction

The catalytic properties, with respect to the 1,3-butadiene hydrogenation reaction, of strained Pd films on Cu(110) (lattice mismatch 8%) has been probed as a function of the film thickness. The characterization of the adlayer has been made by the combined use of STM with LEED and AES. For deposits below 10¹⁵ Pd/cm² (i.e., about 1 ML) the catalytic activity is near zero. This is the consequence of the formation of a Pd–Cu surface alloy with tendency for Cu to migrate/segregate to the surface. The catalytic activity suddenly increases to reach a maximum value for about 3 ML; the activity is then one order of magnitude higher than that of the pure Pd(110) surface. This is the consequence of the presence of a strained Pd overlayer, with Pd surface atoms having very unusual geometry, and hence very peculiar electronic and chemical properties. The catalytic activity then decreases as the Pd coverage is increased, and tends to values near that of the pure Pd(110). Gradual relaxation of the film geometry towards that of the normal fcc Pd structure probably exists.     

钌钯双金属催化剂固载顺序控制及性能

以Al_2O_3、PdCl_2和RuCl_3为原料,采用水溶液浸渍法,通过控制固载顺序、制备流程以及焙烧温度等条件,制得系列负载型Ru Pd双金属催化剂,并用于对苯二甲酸二甲酯(DMT)制取1,4-环己烷二甲酸二甲酯(DMCD)的选择性加氢过程。其中,Ru和Pd的总负载量为0.3%(以催化剂总质量为基准,下同),且m(Ru)∶m(Pd)=1∶1。结果发现,采用先Ru后Pd(Ru-Pd)式固载顺序和浸渍-干燥-浸渍-干燥-焙烧(IDIDC)型制备流程,并在450℃下焙烧后,所得负载型Ru-Pd双金属催化剂的反应性能最佳,在6 MPa、180℃下,DMT转化率为89.6%,DMCD选择性为96.0%,DMCD产率为85.9%。这可能与Ru-Pd中大粒径粒子的形成受到抑制、粒径尺寸和分布更小、比表面积和总孔容更高、表面Pd原子摩尔分数较高以及Ru/Pd物质的量比较低有关。